Apparatus for Thermal Control of Tubing Assembly and Associated Methods

ABSTRACT

Tubing structures are connected to each other to form a tubing assembly having one or more fluid pathways from a fluid entrance to a fluid exit. A heating device is bonded to the tubing structures along a length of the tubing assembly. The heating device has a flexibility to follow along one or more bends present along the length of the tubing assembly. The heating device includes one or more heater traces embedded within an encasing material. The encasing material is thermally conductive and electrically insulative. The one or more heater traces are formed of a material that generates heat in the presence of an electrical current. The heating device has a continuous and unbroken structure along the length of the tubing assembly. An encapsulation layer of thermal insulating material is disposed over the tubing assembly and covers the heating device.

CLAIM OF PRIORITY

This application is a continuation application under 35 U.S.C. 120 ofprior U.S. patent application Ser. No. 15/209,006, filed on Jul. 13,2016, which:

-   -   1) claims priority under 35 U.S.C. 119(e) to U.S. Provisional        Patent Application No. 62/192,560, filed Jul. 14, 2015, and    -   2) is a continuation-in-part (CIP) application under 35 U.S.C.        120 of prior U.S. patent application Ser. No. 14/675,603, filed        Mar. 31, 2015, issued as U.S. Pat. No. 10,139,132, on Nov. 27,        2018.

The disclosure of each above-identified non-provisional and provisionalpatent application is incorporated herein by reference in its entiretyfor all purposes.

BACKGROUND 1. Field of the Invention

The present invention relates to semiconductor chip fabricationfacilities.

2. Description of the Related Art

Many modern semiconductor chip fabrication processes require processgases and/or liquids to be supplied in a carefully controlled manner toa reaction chamber in which the process gases and/or liquids are appliedto affect processing of a semiconductor wafer. Provision of the processgases and/or liquids to the reaction chambers can include controlling atemperature of the process gases and/or liquids in route to the reactionchamber and just prior to input into the reaction chambers. It is withinthis context that the present invention arises.

SUMMARY

In an example embodiment, a tubing assembly is disclosed. The tubingassembly includes a plurality of tubing structures connected to eachother in a configuration providing one or more fluid pathways throughthe plurality of tubing structures from a fluid entrance of theplurality of tubing structures to a fluid exit of the plurality oftubing structures. The tubing assembly also includes a heating devicebonded to the plurality of tubing structures along a length of theplurality of tubing structures in their connected configuration. Theheating device has a flexibility to enable its placement along one ormore bends present along the length of the plurality of tubingstructures in their connected configuration. The heating device includesone or more heater traces embedded within an encasing material. Theencasing material is thermally conductive and electrically insulative.The one or more heater traces is/are formed of a material that generatesheat in the presence of an electrical current. The heating device has acontinuous and unbroken structure along the length of the plurality oftubing structures in their connected configuration. The tubing assemblyalso includes an encapsulation layer of thermal insulating materialdisposed over the plurality of tubing structures and covering theheating device.

In an example embodiment, a method is disclosed for manufacturing atubing assembly. The method includes connecting a plurality of tubingstructures together in a tubing assembly configuration providing one ormore fluid pathways through the plurality of tubing structures from afluid entrance of the tubing assembly configuration to a fluid exit ofthe tubing assembly configuration. The method also includes bonding aheating device to the plurality of tubing structures along a length ofthe tubing assembly configuration. The heating device has a flexibilityto enable its placement along one or more bends present along the lengthof tubing assembly configuration. The heating device includes one ormore heater traces embedded within an encasing material. The encasingmaterial is thermally conductive and electrically insulative. The one ormore heater traces is/are formed of a material that generates heat inthe presence of an electrical current. The heating device has acontinuous and unbroken structure along the length of the tubingassembly configuration. The method also includes applying anencapsulation layer of thermal insulating material over the tubingassembly configuration to cover the heating device.

Other aspects and advantages of the invention will become more apparentfrom the following detailed description, taken in conjunction with theaccompanying drawings, illustrating by way of example the presentinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic top view of an example embodiment of amulti-station processing tool within a semiconductor fabricationfacility.

FIG. 2 shows a flowchart of a method for manufacturing a tubing assemblywith integral heating components, in accordance with some exampleembodiments of the present invention.

FIG. 3 shows an example tubing assembly as connected together inoperation, in accordance with an example embodiment of the presentinvention.

FIG. 4 shows the tubing assembly of FIG. 3 with a layer of high thermalconductivity material applied to the external surfaces of the tubingstructures.

FIG. 5 shows an example heating device configuration, in accordance withsome embodiments of the present invention.

FIG. 6 shows two cut sections of the heating device having their heatertraces electrically connected together, in accordance with some exampleembodiments of the present invention.

FIG. 7 shows the tubing assembly of FIG. 4 with the continuous length ofthe heating device conformally bonded to the tubing assembly, inaccordance with some embodiments of the present invention.

FIG. 8 shows an encapsulation layer of thermal insulating materialdisposed over the tubing assembly so as to cover the heating device.

FIG. 9 shows the tubing assembly of FIG. 8 with a layer of abrasionresistant material applied over the encapsulation layer of thermalinsulating material.

FIG. 10 shows an example fit up of tubing assemblies having integralheating components as manufactured in accordance with the method of FIG.2, in accordance with some example embodiments of the present invention.

DETAILED DESCRIPTION

In the following description, numerous specific details are set forth inorder to provide a thorough understanding of the present invention. Itwill be apparent, however, to one skilled in the art that the presentinvention may be practiced without some or all of these specificdetails. In other instances, well known process operations have not beendescribed in detail in order not to unnecessarily obscure the presentinvention.

FIG. 1 shows a schematic top view of an example embodiment of amulti-station processing tool 100 within a semiconductor fabricationfacility. The multi-station processing tool 100 includes an inbound loadlock 102 and an outbound load lock 104. A robot 106, at atmosphericpressure, is configured to move a substrate, e.g., semiconductor wafer,from a cassette loaded through a pod 108 into inbound load lock 102 viaan atmospheric port 110, and place the substrate on a support 112 withinthe inbound load lock 102. Inbound load lock 102 is coupled to a vacuumsource (not shown) so that, when atmospheric port 110 is closed, inboundload lock 102 may be pumped down. Inbound load lock 102 also includes achamber transport port 116 interfaced with processing chamber 103. Thus,when chamber transport port 116 is opened, another robot (not shown) maymove the substrate from inbound load lock 102 to a substrate support 118of a first process station 1 for processing. The example processingchamber 103 includes four process stations, numbered from 1 to 4. Itshould be appreciated, however, that other embodiments of the processingchamber 103 can include more or less process stations, and can bearranged in configurations different than what is shown by way ofexample for the processing tool 100 in FIG. 1.

In some embodiments, processing chamber 103 may be configured tomaintain a low pressure environment so that substrates may betransferred among the process stations 1-4 within the processing chamber103 using carrier rings 125A-125D and spider forks 126A-126D withoutexperiencing a vacuum break and/or air exposure. The spider forks126A-126D rotate and enable transfer of substrates between processstations. The transfer occurs by enabling the spider forks 126A-126D tolift the carrier rings 125A-125D from an outer undersurface, which liftsthe substrates, and rotates the substrates and carrier rings 125A-125Dtogether to the next process station. Each process station depicted inFIG. 1 includes a process station substrate support 118A-118D andprocess fluid supply lines and removal lines. It should be appreciatedthat the processing tool 100 and each of the process stations 1-4represents a very complex system including numerous interrelated andinterfacing components. In order to avoid unnecessarily obscuring thepresent invention, details of the processing stations 1-4 and otherinterrelated and interfacing components are not further describedherein.

Each process station 1-4 can be defined to perform one or more substrateprocessing/manufacturing operations. The processing/manufacturingoperations performed by the process stations 1-4 can include utilizationof various fluids (gases and/or liquids) which are delivered to andremoved from the process stations 1-4 by various tubing arrangements.For example, with reference back to FIG. 1, within the semiconductorfabrication facility, the spaces between, above, below, around, andwithin the processing tool 100 and its various process stations 1-4 caninclude a complex network of tubing for delivering various process gasesand/or liquids to the various process stations and for removing variousprocess gases and/or liquids from the various process stations 1-4.

In some embodiments, portions of this network of tubing needs to betemperature controlled so as to establish and control temperatures ofthe various process fluids prior to their arrival at the various processstations 1-4. In some embodiments, tubing is heated and insulated toaffect heating of the various process fluids as they travel through thetubing network to the process stations 1-4. In some embodiments, theheating of the tubing is provided by electrical resistance heaters incontact with or in close proximity to the tubing. In such embodiments,the tubing is metallic or made of a material suitable to withstandexposure to the heat flux emanating from the electrical resistanceheaters.

In some embodiments, portions of the tubing network used to conveyvarious process fluids to and/or from the process stations 1-4 arefabricated as separate tubing assemblies outside of the semiconductorfabrication facility. The separate tubing assemblies are then fittogether within the semiconductor fabrication facility to form therequired network of tubing for delivery of various process fluids to theprocess stations 1-4 and/or for removal of various process fluids fromthe process stations 1-4. Some sections or flow paths of the tubingnetwork may need to be temperature controlled. The tubing assemblieswithin these temperature controlled sections of the tubing network canbe fabricated with integral heating components. In some embodiments, theintegral heating components of various tubing assemblies can beconnected together as the various tubing assemblies are fit togetherwithin the semiconductor fabrication facility, so as to form anelectrical heating circuit for sections of the tubing network. And, theelectrical heating circuit can be connected to a control system forcontrolling the heating of the tubing, which in turn controls thetemperature of the fluids being delivered to and/or removed from theprocess stations 1-4.

Some heating devices may be fabricated in fixed lengths for use with anindividual, linear tubing section of corresponding length. With theseheating devices, each linear section of tubing in a multiple tubeassembly will have its own heating device, thereby resulting in multipleheating devices located along the length of the overall tubing assembly.Controlling the locations of adjacent heating devices as well asmanaging the many layers in heating device construction is verylaborious and does not lend itself to automation. Finding a way toimprove the process of manufacturing tubing assemblies with integratedheating capability is necessary for substantial cost reduction. Methodsand structures are disclosed herein for manufacturing a tubing assemblywith an integrated heating capability by attaching a scalable heatingdevice to the tubing assembly. The scalable heating device is notspecific to a given tubing assembly and is manufactured separately fromthe tubing assembly. In some embodiments, the heating device disclosedherein is manufactured in a cut-to-length configuration, such that theheating device can be manufactured in high volume, thereby reducingoverall cost of the final tubing assembly. In some embodiments, thescalable heating device disclosed herein can be constructed in highvolume as a continuous heater tape that does not need to be specific tothe particular tubing assembly, and heater segments can be cut-to-lengthfrom the continuous heater tape as needed during fabrication of a giventubing assembly.

FIG. 2 shows a flowchart of a method for manufacturing a tubing assemblywith integral heating components, in accordance with some exampleembodiments of the present invention. The method includes an operation201 for connecting a plurality of tubing structures together in a tubingassembly configuration providing one or more fluid pathways through theplurality of tubing structures from a fluid entrance of the plurality oftubing structures to a fluid exit of the plurality of tubing structures.FIG. 3 shows an example tubing assembly as connected together inoperation 201, in accordance with an example embodiment of the presentinvention. The tubing assembly 300 includes tubing structures 305, 307,309, 311, 313, 315, 317, 319, 321, 323, and 325 connected together toprovide a fluid pathway through the tubing assembly 300 from a fluidentrance 301 to a fluid exit 303. In some embodiments, the tubingstructures of the tubing assembly 300 are welded together to form aweldment. However, in other embodiments, some or all of the tubingstructures can be connected together using non-welding techniques, suchas by brazing or soldering. Also, in some embodiments, one or more ofthe tubing structures can include an end flange structure to provide forassembly using a gasket/seal-ring and fasteners such as bolts.

It should be understood that the number of tubing structures and theirconfiguration as depicted in the tubing assembly 300 of FIG. 3 is forpurposes of description and is not intended to place any limit orrestriction on how the tubing assembly can be configured in operation201. The tubing assembly configuration as connected together inoperation 201 can include any number of tubing structures, any shape oftubing structure, and any size of tubing structure, and can be puttogether using any assembly/connection process. In some embodiments,however, the tubing assembly configuration as connected in operation 201includes at least two tubing structures that are connected within thetubing assembly in an angled configuration relative to each other suchthat an angle of less than 180 degrees exists between axial centerlinesof the at least two tubing structures. For example, the tubing assembly300 of FIG. 3 shows tubing structures 307 and 311 that are connected atan angled configuration relative to each other such that an angle 327 ofless than 180 degrees exists between their axial centerlines.

In some embodiments, operation 201 is performed under a constraint thatbends and/or fittings in the tubing assembly can only be located atpredetermined spacings along the length of the tubing assembly, whereeach predetermined spacing corresponds to an integer multiple of a unitcut length of a heating device to be attached to the tubing assembly.For example, if the unit cut length of the heating device is one inch,then the predetermined spacings for locating bends and/or fittings alongthe length of the tubing assembly is an integer multiple of one inch,i.e., an integer number of inches. As another example, if the unit cutlength of the heating device is one-half inch, then the predeterminedspacings for locating bends and/or fittings along the length of thetubing assembly is an integer multiple of one-half inch. It should beunderstood that the unit cut length of one inch and one-half inch areprovided by way of example. In other embodiments, the unit cut length ofthe heating device can be essentially any size.

The method of FIG. 2 continues with an optional operation 203 in which alayer of high thermal conductivity material is applied to the tubingassembly as formed in operation 201. For example, in some embodiments,“cold spray” coating technology is used to apply a layer of high thermalconductivity material such as copper or aluminum to the tubing assembly.The high thermal conductivity material has a greater thermalconductivity than the material of which the tubing assembly is formed,e.g., stainless steel. The high thermal conductivity material applied inoperation 203 provides enhanced heat transfer around the circumferenceof the tubing and fittings that compose the tubing assembly, therebyallowing the method of heating the tubing assembly to be less preciseand still achieve a high quality and uniform heating of the tubingassembly. Additionally, in some embodiments, a superior adhesion ofcopper to stainless steel can be achieved such that a vacuum-tightjunction is formed between the applied copper and the stainless steel ofthe tubing assembly. The “cold spray” coating method is highly conformaland provides rapid deposition rates, e.g., of approximately 0.5 inch perminute or more.

FIG. 4 shows the tubing assembly 300 of FIG. 3 with a layer of highthermal conductivity material 400 applied to the external surfaces ofthe tubing structures 307, 309, 311, 313, 315, 317, 319, 321, 323. Insome embodiments, the operation 203 can be performed to apply the layerof the high thermal conductivity material to some of the tubingstructures while not applying the layer of the high thermal conductivitymaterial to some of the tubing structures. For example, FIG. 4 showsthat the layer of the high thermal conductivity material is not appliedto the tubing structures 305 and 325. In some embodiments, the operation203 can be performed to apply the layer of the high thermal conductivitymaterial to all of the tubing structures.

The method of FIG. 2 continues with an operation 205 in which acontinuous length of the heating device is cut to fit along the lengthof the tubing assembly. The length of the heating device takes intoaccount bends and fittings present along the length of the tubingassembly. As previously mentioned, the heating device is configured tobe cut at an interval of the unit cut length. The heating device isconfigured to be flexible to provide for placement of the heating devicealong the bends and contours of the tubing assembly. In someembodiments, the heating device can include narrow copper tracesembedded in polyimide to provide sufficient flexibility of the heatingdevice in order to follow the bends and contours of the tubing assembly.The heating device can also include multiple conductor traces, e.g.,copper traces, to provide for increased thermal output per unit lengthof the heating device.

FIG. 5 shows an example heating device 500 configuration, in accordancewith some embodiments of the present invention. In the example of FIG.5, the heating device 500 has a serpentine configuration formed byregularly spaced slits 511 located at opposing sides of the heatingdevice 500 in an alternating manner along its length direction (L). Theslits 511 provide the heating device 500 with flexibility to enablepositioning of the heating device 500 along the bends and contours ofthe tubing assembly. The heating device 500 includes conductiveresistance heater traces 501A and 501B embedded within an encasingmaterial that is thermally conductive and electrically insulative. Insome embodiments, the encasing material is polyimide. In otherembodiments, the encasing material of the heating device 500 in whichthe heater traces 501A and 501B are embedded can be formed of anelectrically insulative, thermally conductive, and sufficiently flexiblematerial other than polyimide. The heater traces 501A and 501B arearranged in an adjacent and substantially parallel manner to each otherfollowing along the serpentine shape of the heating device 500. In someembodiments, the resistance heater traces 501A and 501B are configuredas narrow copper traces embedded in polyimide. Also, in otherembodiments, the heater traces 501A and 501B can be formed of anotherelectrically conductive and sufficiently flexible material suitable foruse as an electrical resistance heating element, such as Nichrome, whichis a non-magnetic alloy of nickel and chromium having a high resistivityand resistance to oxidation at high temperature, or Constantan, which isa copper-nickel alloy having a substantially constant resistivity over abroad range of temperature, or Kanthal™, such as Alloy 875/815, which isa family of alloys of iron-chromium-aluminum having intermediateelectrical resistance and an ability to withstand high temperatures, orEvanohm (Alloy 800), or Advance™ (Cupron or Alloy 45), or Midohm™ (Alloy180), or Balco (Alloy 120), or Alloy 30, or Alloy 60, or Alloy 90, amongothers.

FIG. 5 also shows that the example heating device 500 is configured in acut-to-length manner, having a unit cut length 513. Each unit cut lengthof the heating device 500 includes heater trace access locations 503Aand 503B to enable electrical contact access to each of the heatertraces 501A and 501B, respectively. The heater trace access locations503A and 503B provide for connection of external conductors to theheater traces 501A and 501B. For example, external conductors 505 and507 for connection to positive and negative terminals, respectively, ofa power supply can be connected to the heater traces 501A and 501B atone end of the heating device 500 by way of the heater trace accesslocations 503A-1 and 503B-1. Also, an external conductor 509 can beconnected to the heater traces 501A and 501B at the other end of theheating device 500 by way of the heater trace access locations 503A-2and 503B-2, so as to complete the electrical circuit through the heatingdevice 500.

Also, in some embodiments, the heater trace access locations 503A and503B can be used to connect separate cut sections of the heating device500. For example, FIG. 6 shows two cut sections of the heating device500A and 500B having their heater traces 501A and 501B electricallyconnected together, in accordance with some example embodiments of thepresent invention. The heater trace 501A of heating device 500A iselectrically connected to the heater trace 501A of heating device 500Bthrough a conductor 601 by way of heater trace access locations 503A-2and 503A-3. Similarly, the heater trace 501B of heating device 500A iselectrically connected to the heater trace 501B of heating device 500Bthrough a conductor 603 by way of heater trace access locations 503B-2and 503B-3. Also, in the example of FIG. 6, an external conductor 605 isconnected to the heater traces 501A and 501B at the other end of theheating device 500B by way of the heater trace access locations 503A-4and 503B-4, so as to complete the electrical circuit through thecombination of heating devices 500A and 500B.

With reference back to FIG. 2, the method continues with an operation207 for bonding the continuous length of heating device, e.g., heatingdevice 500, as cut in operation 205 to the tubing assembly along thelength of the tubing assembly. In the embodiment using the exampleheating device 500 of FIG. 5, the serpentine configuration of theheating device 500 enables conformal bonding of the heating device 500to the geometry of the tubing assembly, including around swept bends andfittings along the length of the tubing assembly. FIG. 7 shows thetubing assembly 300 of FIG. 4 with the continuous length of the heatingdevice 500 conformally bonded to the tubing assembly 300, in accordancewith some embodiments of the present invention. In the embodiment inwhich the high thermal conductivity material 400 is applied to theexternal surfaces of the tubing assembly 300, the continuous length ofthe heating device 500 is conformally bonded to the high thermalconductivity material 400. In the embodiment in which the high thermalconductivity material 400 is not applied to the external surfaces of thetubing assembly 300, the continuous length of the heating device 500 isconformally bonded directly to the tubing material of the tubingassembly 300.

The method of FIG. 2 continues with an operation 209 for connecting endleads to the continuous length of heating device 500, as needed. Forexample, FIG. 7 shows the conductors 505 and 507 from FIG. 5 connectedas end leads to the heating device 500. Also, FIG. 7 shows the conductor509 from FIG. 5 connected as a bridging wire to connect the heatertraces 501A and 501B. In some embodiments, the end leads are soldered tothe heating device 500 in operation 209.

The method of FIG. 2 continues from operation 209 with an optionaloperation 211 for applying a layer of dielectric material onto thecombination of the tubing assembly and the heating device. In someembodiments, the dielectric material applied in the operation 211 can beboth electrically insulating and thermally conductive. In someembodiments, the dielectric material applied in the operation 211 can bepolyimide. In some embodiments, the dielectric material applied in theoperation 211 can be both electrically insulating and thermallyinsulating. It should be appreciated that the dielectric materialapplied in the operation 211 can be essentially any type of dielectricmaterial that is capable of providing a required amount of electricalinsulation. In various embodiments, the dielectric material can beapplied in the operation 211 to have a thickness with a range extendingfrom about 10 microns to about 500 microns. However, it should beunderstood that in other embodiments the dielectric material can beapplied in the operation 211 to have a thickness greater than 500microns.

The method of FIG. 2 continues with an operation 213 for applying anencapsulation layer of thermal insulating material over the tubingassembly in a manner to cover the heating device 500 as bonded to thetubing assembly in the operation 207, while leaving electrical leads ofthe heating device 500 exposed, i.e., not covered by the encapsulationlayer of thermal insulating material. For example, FIG. 8 shows anencapsulation layer of thermal insulating material 801 disposed over thetubing assembly 300 so as to cover the heating device 500, while leavingelectrical leads of the heating device 500 exposed. In variousembodiments, the encapsulation layer of thermal insulating material 801applied in the operation 213 can be formed of silicon rubber or othertype of synthetic material containing a low amount of volatile organiccompounds (VOCs) and/or having a pore size that will not trap VOCs,among others. In some embodiments, the encapsulation layer of thermalinsulating material 801 applied in the operation 213 can be formed offoam structures, rubber structures, and/or silicon structures, havinglow VOC content, among others. In some embodiments, the encapsulationlayer of thermal insulating material 801 is also a dielectric material.In various embodiments, the encapsulation layer of thermal insulatingmaterial 801 can be applied in the operation 213 to have a thicknesswith a range extending from about 1 millimeter (mm) to about 14 mm. Insome embodiments, the encapsulation layer of thermal insulating material801 can be applied in the operation 213 to have a thickness of about 6mm.

Also, the method can include an optional operation 215 for applying alayer of an abrasion resistant material over the encapsulation layer 801that was applied in operation 213. In some embodiments, the operation215 is performed to apply the layer of abrasion resistant material overportions of the encapsulation layer 801 where abrasion resistance isrequired once the tubing assembly is fit up within the semiconductorfabrication facility. In some embodiments, the operation 215 isperformed to apply the layer of abrasion resistant material over anentirety of the encapsulation layer 801. For example, FIG. 9 shows thetubing assembly 300 of FIG. 8 with a layer of abrasion resistantmaterial 901 applied over the encapsulation layer of thermal insulatingmaterial 801. In various embodiments, the layer of abrasion resistantmaterial 901 applied in the operation 215 can be formed of flexiblematerial, such as polyimide, nylon, silicon, fiber-reinforced silicon,and/or Kevlar™, among others. In some embodiments, the layer of abrasionresistant material 901 applied in the operation 215 can be formed as ajacket covering or as a mesh sleeve or as a tube. In variousembodiments, the layer of abrasion resistant material 901 can be appliedin the operation 215 to have a thickness with a range extending fromabout 50 microns to about 400 microns. In some embodiments, the layer ofabrasion resistant material 901 can be applied in the operation 215 tohave a thickness up to about 5 mm.

FIG. 10 shows an example fit up of tubing assemblies having integralheating components as manufactured in accordance with the method of FIG.2, in accordance with some example embodiments of the present invention.Specifically, FIG. 10 shows a first tubing assembly 1002 fit togetherwith a second tubing assembly 1004. For sake of description, each of thetubing assemblies 1002 and 1004 is like the previously described tubingassembly 300. It is envisioned that each of the tubing assemblies 1002and 1004 is fabricated outside of the semiconductor fabrication facilityand then fit together inside the semiconductor fabrication facility ator near their final place of installation. In the example configurationof FIG. 10, the heating device 500-1 of the first tubing assembly 1002is electrically connected to the heating device 500-2 of the secondtubing assembly 1004 through the conductors 601A, 601B, 603A, and 603B,in the manner as previously discussed with regard to FIG. 6. In someembodiments, an electrical connector 1021 is used to electricallyconnect the conductor 601A to the conductor 601B, and to electricallyconnect the conductor 603A to the conductor 603B. Also, the heatertraces of the heating device 500-2 are electrically connected to eachother through the conductor 605, in the manner as previously discussedwith regard to FIG. 6. And, the heater traces of the heating device500-1 are electrically connected to the conductors 505 and 507,respectively, in the manner as previously discussed with regard to FIGS.5 and 6, with the conductors 505 and 507 respectively connected to twoprongs of an electrical connector 1023, which is in turn electricallyconnected to an electrical connector 1011 of a power supply line 1025.

The power supply line 1025 includes two separate electrical conductors1007 and 1009 that run to a power supply 1001. In the example of FIG.10, the power supply 1001 is a direct current (DC) power supply andincludes a positive terminal 1003 and a negative terminal 1005. Theelectrical conductor 1007 is electrically connected to the positiveterminal 1003, and the electrical conductor 1009 is electricallyconnected to the negative terminal 1005. The power supply 1001 isdefined to provide a flow of electric current through the heater tracesof the heating devices 500-1 and 500-2, which in turn causes heating ofthe tubing structures within each of the first and second tubingassemblies 1002 and 1004, which in turn causes heating of the fluidtraveling through the first and second tubing assemblies 1002 and 1004.The power supply 1001 is defined to provide the flow of electric currentthrough the heater traces of the heating devices 500-1 and 500-2 in acontrolled manner to as maintain a target temperature of the first andsecond tubing assemblies 1002 and 1004, and correspondingly of the fluidtraveling through the first and second tubing assemblies 1002 and 1004.It should be understood that although the power supply 1001 is shown asa DC power supply in the example embodiments of FIG. 10, in otherembodiments the power supply 1001 can be an alternating current (AC)power supply, with the positive and negative terminals 1003 and 1005representing electrical terminals of the AC power supply.

FIG. 10 also shows that in some embodiments a temperature control system1013 can be implemented to provide for control of the temperature of thetubing assemblies 1002 and 1004. The temperature control system 1013 canbe connected to receive inputs from a number of thermocouple leads1015A, 1015B (or essentially any other type of temperature sensingdevice) deployed to measure the temperature of the tubing assemblies1002 and 1004. It should be appreciated that any number of temperaturesensors can be deployed at any location on the tubing assemblies 1002and 1004 as necessary to provide temperature inputs required forcontrolling the temperature of the fluid flowing through the tubingassemblies 1002 and 1004. The temperature control system 1013 isconfigured to transmit control signals to the power supply 1001, by wayof connection 1017, so as to control the power supply 1001 based on themonitored temperature inputs (as received through 1015A, 1015B) so as tocontrol the heating provided by the two heating devices 500-1 and 500-2,and thereby control the temperature of the fluid flowing through thetubing assemblies 1002 and 1004.

It should be understood that the example system depicted in FIG. 10 is asimplified example provided for descriptive purposes. In variousembodiments, any number and any configuration of tubing assemblies asmanufactured in accordance with the method of FIG. 2 can be fit togetherin the semiconductor fabrication facility. Also, in some embodiments,one or more power supplies, e.g., 1001, can be connected to provideelectrical power to any number of and any configuration of heatingdevices 500 of tubing assemblies as manufactured in accordance with themethod of FIG. 2, as necessary to appropriately heat the fluid flowingthrough the tubing assemblies.

Based on the description presented herein, it should be understood thata tubing assembly is disclosed as including a plurality of tubingstructures connected to each other in a configuration providing one ormore fluid pathways through the plurality of tubing structures from afluid entrance of the plurality of tubing structures to a fluid exit ofthe plurality of tubing structures. In some embodiments, the pluralityof tubing structures are welded together to provide the one or morefluid pathways through the plurality of tubing structures. However, inother embodiments, the plurality of tubing structures can be connectedtogether using methods other than welding, such as with seals andfasteners. Also, in some embodiments, the plurality of tubing structuresincludes at least two tubing structures that are connected within thetubing assembly at an angled configuration relative to each other suchthat an angle of less than 180 degrees exists between axial centerlinesof the at least two tubing structures. A heating device is bonded to theplurality of tubing structures along a length of the plurality of tubingstructures in their connected configuration. The heating device has aflexibility to enable its placement along one or more bends presentalong the length of the plurality of tubing structures in theirconnected configuration. The heating device includes one or more heatertraces embedded within an encasing material. The encasing material isthermally conductive and electrically insulative. The one or more heatertraces is/are formed of a material that generates heat in the presenceof an electrical current. The heating device has a continuous andunbroken structure along the length of the plurality of tubingstructures in their connected configuration. And, an encapsulation layerof thermal insulating material is disposed over the plurality of tubingstructures and covers the heating device. Also, in some embodiments, alayer of an abrasion resistant material is disposed over theencapsulation layer of thermal insulating material.

In some embodiments, a layer of a thermally conductive material isconformally disposed on the plurality of tubing structures so as tocircumferentially cover the plurality of tubing structures. In theseembodiments, the heating device is bonded to the layer of thermallyconductive material along the length of the plurality of tubingstructures in their connected configuration, and the encapsulation layerof thermal insulating material is disposed to cover the layer ofthermally conductive material and the heating device. In someembodiments, the layer of thermally conductive material is applied tothe plurality of tubing structures using a cold spray coatingapplication. In some embodiments, the layer of thermally conductivematerial is copper and the plurality of tubing structures are formed ofstainless steel. In some embodiments, the layer of thermally conductivematerial is aluminum and the plurality of tubing structures are formedof stainless steel.

In some embodiments, a layer of a dielectric material is conformallydisposed on the plurality of tubing structures so as tocircumferentially cover the plurality of tubing structures. In theseembodiments, the layer of dielectric material is disposed to cover thelayer of thermally conductive material, when present, and the heatingdevice. Also, the encapsulation layer of thermal insulating material isdisposed to cover the layer of dielectric material.

In some embodiments, the heating device is configured in a cut-to-lengthmanner to enable cutting of a length of the heating device to fit thelength of the plurality of tubing structures in their connectedconfiguration. In some embodiments, the heating device includes twoheater traces embedded within the encasing material, with the two heatertraces positioned in a substantially parallel relationship to each otheralong the length of the heating device. Also, in some embodiments, abridging wire is electrically connected to each of the two heater tracesat a first end of the heating device, and a first electrical lead iselectrically connected to a first of the two heater traces at a secondend of the heating device, and a second electrical lead is electricallyconnected to a second of the two heater traces at the second end of theheating device. The first and second electrical leads are configured forrespective connection to positive and negative terminals of anelectrical power supply.

Additionally, in some embodiments, the heating device is configured tohave a serpentine shape along the length of the heating device, such asdescribed with regard to FIG. 5. The serpentine shape increases anamount of the two heater traces present per unit length along the lengthof the plurality of tubing structures in their connected configuration.The serpentine shape also enables flexibility of the heating device,such that the heating device can be positioned along bends within thetubing assembly. It should be understood, however, that in otherembodiments the heating device may not have a serpentine shape, e.g.,may rather have a tape-like shape, but will still have sufficientflexibility to be positioned along bends within the tubing assembly.

The cost structure of conventional heating device supply andinstallation for tubing weldments is dominated by the manual labornecessary to: 1) engineer many layers in the construction of aconventional heater jacket that is designed specifically for aparticular tubing weldment with little opportunity for reusability, and2) program the cutting, and 3) have the layers cut as needed, and mostimportantly 4) aligning the heating devices and bond them together. Itshould be understood that the present invention provides improvedmethods and systems for heating a fluid-carrying tubing weldment, i.e.,tubing assembly, by bonding a cut-to-length, flexible, heating device tothe tube weldment, with encapsulation of the bonded heating device by athermal insulator. The flexible, cut-to-length heating device, e.g.,heating device 500, can be manufactured in bulk quantity, perhaps in aroll configuration, without consideration of any particular tubingassembly to which the heating device will ultimately be applied. Thisindependent heating device manufacturing capability provides forsignificant cost savings in comparison with the above-mentioned coststructure of conventional heating device supply and installation.

It should also be appreciated that the method for manufacturing tubingassemblies with integral heating components as disclosed herein providesfor relief of component crowding within tight spaces around and near thetubing assemblies when installed in the semiconductor fabricationfacility. For example, by integrating heating components within thetubing assemblies, in the manner disclosed herein, the number ofelectrical connections for heating the tubing network is reduced, whichthereby reduces component crowding that would have otherwise been causedby an excessive number of electrical connections. Also, by reducing thenumber of required electrical connections and correspondingly reducingthe component crowding around and near where the tubing assemblies areto be installed within the semiconductor fabrication facility, theinstallation of the tubing assemblies having the integral heatingcomponents is simplified. Also, integration of the heating componentswith the tubing assemblies, as disclosed herein, lends itself toautomation, as disclosed herein, which in turn can lead to reduced costfor temperature controlled tubing networks within the semiconductorfabrication facility.

The foregoing description of the embodiments has been provided forpurposes of illustration and description. It is not intended to beexhaustive or to limit the invention. Individual elements or features ofa particular embodiment are generally not limited to that particularembodiment, but, where applicable, are interchangeable and can be usedin a selected embodiment, even if not specifically shown or described.The same may also be varied in many ways. Such variations are not to beregarded as a departure from the invention, and all such modificationsare intended to be included within the scope of the invention.

Although the foregoing invention has been described in some detail forpurposes of clarity of understanding, it will be apparent that certainchanges and modifications can be practiced within the scope of theappended claims. Accordingly, the present embodiments are to beconsidered as illustrative and not restrictive, and the invention is notto be limited to the details given herein, but may be modified withinthe scope and equivalents of the described embodiments.

What is claimed is:
 1. A heating device, comprising: an encasingmaterial that is thermally conductive and electrically insulative, theencasing material having a serpentine shape that is substantiallyrectangularly bounded, such that the heating device has the serpentineshape along a length of the heating device; and at least one heatertrace embedded within the encasing material, the at least one heatertrace formed of a material that generates heat in the presence of anelectrical current.
 2. The heating device as recited in claim 1, whereinthe encasing material is flexible.
 3. The heating device as recited inclaim 1, wherein the encasing material includes polyimide.
 4. Theheating device as recited in claim 1, wherein the at least one heatertrace is formed from an alloy comprising at least one metal, wherein ametal of the at least one metal is selected from a group consisting ofcopper, iron, nickel, chromium, aluminum, molybdenum, tungsten,manganese, and cobalt.
 5. The heating device as recited in claim 1,wherein the heating device is configured in a cut-to-length manner. 6.The heating device as recited in claim 1, wherein the heating device isconfigured as a contiguous plurality of unit cut lengths, each unit cutlength including heater trace access locations for respective electricalconnection to each of the at least one heater trace.
 7. The heatingdevice as recited in claim 6, wherein the unit cut lengths areconfigured to enable cutting of a length of the heating device to fit alength of a plurality of tubing structures in their connectedconfiguration.
 8. The heating device as recited in claim 1, wherein theserpentine shape of the encasing material increases an amount of the atleast one heater trace present per unit length of the heating device. 9.The heating device as recited in claim 1, wherein the serpentine shapeof the encasing material enables flexibility of the heating device. 10.The heating device as recited in claim 1, wherein the serpentine shapeof the encasing material is formed by regularly spaced slits located atopposing sides of the heating device in an alternating manner along thelength of the heating device.
 11. The heating device as recited in claim10, wherein the regularly spaced slits are configured to enableflexibility of the heating device.
 12. The heating device as recited inclaim 10, wherein adjacently positioned slits of the regularly spacedslits along the length of the heating device include a first slit and asecond slit, the first slit extending across the heating device from afirst side of the heating device, the second slit extending across theheating device from a second side of the heating device.
 13. The heatingdevice as recited in claim 12, wherein a portion of the first slitextends past a portion of the second slit.
 14. The heating device asrecited in claim 12, wherein the first and second slits extend acrossthe heating device in a substantially parallel manner.
 15. The heatingdevice as recited in claim 14, wherein a portion of the first slitextends past a portion of the second slit.
 16. The heating device asrecited in claim 1, wherein the at least one heater trace is two heatertraces.
 17. The heating device as recited in claim 16, wherein the twoheater traces are positioned in a substantially parallel relationship toeach other along the serpentine shape of the encasing material.
 18. Theheating device as recited in claim 17, further comprising: a bridgingwire electrically connected to each of the two heater traces at a firstend of the heating device; a first electrical lead electricallyconnected to a first of the two heater traces at a second end of theheating device; and a second electrical lead electrically connected to asecond of the two heater traces at the second end of the heating device,the first and second electrical leads configured for respectiveconnection to positive and negative terminals of an electrical powersupply.
 19. The heating device as recited in claim 18, wherein theheating device is a first heating device, wherein the first electricallead is connected to a first of two heater traces of a second heatingdevice, the second heating device configured in a same manner as thefirst heating device, and wherein the second electrical lead iselectrically connected to a second of the two heater traces of thesecond heating device.
 20. The heating device as recited in claim 17,wherein the serpentine shape of the encasing material is formed by aplurality of slits, wherein each adjacently positioned pair of slits ofthe plurality of slits along the length of the heating device includes afirst slit and a second slit, the first slit extending across theheating device from a first side of the heating device, the second slitextending across the heating device from a second side of the heatingdevice, wherein a portion of the first slit extends past a portion ofthe second slit, and wherein the two heater traces are routed betweenthe first slit and the second slit.